When Pope Innocent VIII planned the anti-Turkish crusade, he focused particular attention on the countries of Central and Eastern Europe: Poland, Lithuania, the Czech Republic and Hungary. However, unlike his predecessors, who rather unilaterally supported the Hungarian king Matthias Corvinus in his conflicts with the Jagiellonians and Habsburgs, Innocent remained in very tense relations with Hungary for several years. The problem of the crusade was to be finally resolved at the anti-Turkish congress in Rome in 1490. At this congress, Poland intended to make a special contribution to the fight against the Turks and, in return, obtain a cardinal's hat for the king's son, Frederick. With the death of King Matthias in 1490, the plans of Poland and the papacy failed. The Jagiellonians joined the fight for the Hungarian throne, and the pope, after the death of the energetic king of Hungary, who was to lead the crusade, decided to enter into negotiations with Sultan Bajazet II. The anti-Turkish Congress did develop plans for a pan-European campaign against the Turks, but European rulers could not be persuaded to take any concrete action.